Dtjstrie akteengesellschaft



Patented den. 15, 1929,

, UNITED STATES wimnnm sans Ann nonnnrenmssnaon, or nnnwrssnarnnron-zrnn-nmnnrin PATENT, oFFICu;

OTTO SCHLIE1HAKE,.OF-MANNHEIM, GERMANY, ASSIGNORS TO I. G. FA RBENII N- DUSTBIE AKTIENGESELLSCHAFT, F FRANKFORT-ONTHE-MAIN, GERMANY, A COB-- IPORATION OF GERMANY;

rnocnss non MAKING MIXED FERTILIZER.

1T0 Drawing. Application filed January 17, 1928, Serial No. 247,452, and in Germany January 21, 1927;

This invention relates to the production of high grade mixed fertilizers, which are free from useless ballast materials such as hydrochloric and sulfuric acid radicals, sodium,

calcium and the like. a

We have found that a high grade mixed fertilizer without ballast and consisting substantially of amixture of at least two of the salts potassium nitrate, ammonium nitrate,

10 ammonium phosphate and potassium phos-' phate, but which mixture must contain both ammonium and potassium, is obtained by decomposing potassium fluosilicate, obtained from potassium chlorid as described below, with aqueous ammonia and treating the resulting solution of potassium fluorid and ammonium fluorid with a solution of calcium nitrate with or without phosphoric acid, -or

The process consists in detail of the following stages The production of potassium fluosilicate from potassium chlorid takes place according to the equat1on:

The potassium fluosilicate may also beprepared with minerals containing alumina such as .bauxite, kaolin, slags and the like by converting these substances into aluminium fiuosilicate according. to the following equa- 40 tions a 4 The resulting sparingly soluble potassiumfluosilicate may be readily separated from the calcium chlorid solution resulting according to Equation 1, or from the aluminium chlorid solution resulting according to Equation II. y

The precipitate is washed, and is then decomposed with aqueous ammonia, hydrated Ysilica being deposited anda solution of potassium fluorid and ammonium fluorid obtained, I,

according to the equation 1n. K SiF 41 n, 4H O=Si on), 21m 4mm. The hydrated silica is filtered off, and may be used again for converting a fresh batch of potassium chloridaccording to Equation or" for the productionof fiuosilicic acid according to Equation 11?. v

The potassium-ammonium fluorid solution, which is generally ammoniacal, is then treated with a suitable quantity of a solution obtained by decomposing crude phosphate with nitric acid, the treatment being continued until all the fluorine hasbeen precipitated as calcium. fluorid, according to the equations:

The phosphate solution needed forconverting the potassium-ammonium fluorid solutions is prepared, for example, by dissolving raw phosphate in nitric acid, according'to the equations The resulting solution of calcium nitrate and phosphoric acid or mono-calcium phosphate isneutralized,if necessar and is preferably freed from insoluble resi ues by filtration.

The process accordingto the present inventionis capable of numerous modifications,

which enable the potassiumaphosphorous- V nitrogenratio, and also the ratio of ammoniacal nitrogen nitrate nitrogen, to be varied within Wide Thus,"for example, in order tomodify the phosphorous content, a portion of the nitric acid used for 'decocigposing the raw phos phate may be repla by sulfuric acid or a portion of the phosphoric acid may be removed beforehand from the decomposed raw phosphate by precipitation withammonia,

Moreover, the proportion of potassium may be increased-by 'ope'rating so as to form potassium nitrate according to the equation the excess of ammonium nitrate being easily removed; wholly or in part, if desired. The

- operation may, if desired, be conducted so that monoalkali phosphate is formed instead of dialkaliphosphate.

The al p um chloridsolution obtainable according to nation II? may be employed for the production of'alumina according to the following equation i' p w. 2A 1c1.+eNH.oH-a1. orn,+emnci The process herein described ofiers, inter aha, the important industrial advantage that .1 all conversions -are carriedout'in aqueous soener lutiimLmd' without any pgmatweilhgpenditum of atweclg a -1. .1110 Process for the production of ahi'gh i grade mind fertilize? free from ballast, oom'-.

' at least two 0 thesalts potassium nitrate, ammonium nitrate, potassium phosphate,- ammonium phosphate, and Which'must contain ammomum' and potassium,

which consists-iii decomposing potassium fluosilicateobtained frhm potassium chlorid,

with aqueousammonia intoa-solution of potassium fluorid and ammonium fluorid "and converting this by means of a solution comprising calcium nitrate.

2. The process for the production of a high grade mixed fertilizer free from ballastcomprising at least two of the salts potassium nitrate, ammonium nitrate, potassium phosphate, ammonium phos hate, and which mustcontain both ammonium and potassium,

which, consists in decomposing potassium fluosilicate,'obtained from potassium chlorid,

with aqueous ammonia into a solution of potassium fluorid and ammonium fluorid and convertin this by means of a solution comprising c cium nitrate and phosphoric acid.

3. The process for reduction of a high grade mixed fertilizer rec fromballast comprising-at least two of the salts potassium nitrate, ammonium nitrate, potassium phostrate, ammonium-nitrate,

phosphate, according to the equaphate, ammonium phosphate, and which must' contain J both. ammonium and potassium, which consists in actin with a mixture of calcium fluorid, silica aci and hydrochloric acid on potasium chlorid, decomposing'the re- 'sulting potassium fluosilicate with a ueous ammonia into a solution of otassium uorid and --'ammonium fluorid an converting this by. means of a solution comprising calcium nitrate;

4. The process for the productionof a high:

grade mixed fertilizer free from ballast comprising at-least two-oi the salts potassium ni- 4 phate, ammonium phos'phate,andwhich must contain both. ammomunr and 1 which consistsin actin "with amixture of calcium fluorid,- silicic aci and hydrochloric acid I on potassium chlorid, decomposing the resulting potasium fluosilicate with moma into a solution oipotassium uorid and trate andphosphoric acid: reduction of a high 5. The process for the 1) grade mixed fertilizer freefrom'ballast comprising at least two of the salts potassium nitrate, ammonium nitrate, potassium phos phate, ammonium phosphate,-and which must ueous ampotassium jphosammonium fluorid and centre this by means of a solution comprising cium m-.'

contain both ammonium and potassium,

which consists in acting with aluminium fluosilicate, obtainable from kaolin and hydro-- fluo-sihcic acid, on potassium chlorid, dccomposing the resulting potassium fluo'silicate withaque'ous ammonia into a solution of potassium fluorid and ammonium fluorid and this by means of a solution com-- converti prising ca cium nitrate.

. 6. The forthe production of a grade mixed fertilizer free from ballast com prising at least two of'the salts potassium nitrate, ammonium nitrate, potassium phosphate, ammonium phosphate, and which must contam' both ammonium and' potassium,

which consists in acting with aluminium fluosilicate, obtainable from koalin and hydrofluo-silicic a'cid, on potassium chlorid, decomposing the resulting potassium fluosilicate 5 with aqueous ammonia into a solution of potassium fluorid and ammonium fluorid and converting this by means of a solution comprising calcium nitrate and phosphoric acid. In testimony whereof we have hereunto set our hands.-

WILHELM GAUS. ROBERT GRIESSBACH. OTTO SCHLIEPHAKE. 

